How to send a progress of operation in a FastAPI app?

Question

I have deployed a fastapi endpoint,

from fastapi import FastAPI, UploadFile
from typing import List

app = FastAPI()

@app.post(\'/work/test\')
async def testing(         


        

Answer 1

Below is solution which uses uniq identifiers and globally available dictionary which holds information about the jobs:

NOTE: Code below is safe to use until you use dynamic keys values ( In sample uuid in use) and keep application within single process.

1. To start the app create a file main.py
2. Run uvicorn main:app --reload
3. Create job entry by accessing http://127.0.0.1:8000/
4. Repeat step 3 to create multiple jobs
5. Go to http://127.0.0.1/status page to see page statuses.
6. Go to http://127.0.0.1/status/{identifier} to see progression of the job by the job id.

Code of app:

from fastapi import FastAPI, UploadFile
import uuid
from typing import List


import asyncio


context = {'jobs': {}}

app = FastAPI()



async def do_work(job_key, files=None):
    iter_over = files if files else range(100)
    for file, file_number in enumerate(iter_over):
        jobs = context['jobs']
        job_info = jobs[job_key]
        job_info['iteration'] = file_number
        job_info['status'] = 'inprogress'
        await asyncio.sleep(1)
    pending_jobs[job_key]['status'] = 'done'


@app.post('/work/test')
async def testing(files: List[UploadFile]):
    identifier = str(uuid.uuid4())
    context[jobs][identifier] = {}
    asyncio.run_coroutine_threadsafe(do_work(identifier, files), loop=asyncio.get_running_loop())

    return {"identifier": identifier}


@app.get('/')
async def get_testing():
    identifier = str(uuid.uuid4())
    context['jobs'][identifier] = {}
    asyncio.run_coroutine_threadsafe(do_work(identifier), loop=asyncio.get_running_loop())

    return {"identifier": identifier}

@app.get('/status')
def status():
    return {
        'all': list(context['jobs'].values()),
    }

@app.get('/status/{identifier}')
async def status(identifier):
    return {
        "status": context['jobs'].get(identifier, 'job with that identifier is undefined'),
    }